Fixed-measurement-point-free pose adjustment and positioning method for large-scale three-dimensional assembly

Abstract

A fixed-measurement-point-free pose adjustment and positioning method for large-scale three-dimensional assembly. According to the method, by using a fixed-measurement-point-free mode, the need for the step of arranging measurement points on each plane of a three-dimensional part (3) in the early stage is eliminated, improving the measurement efficiency for the three-dimensional part (3) while mitigating the impact of over-constrained point positions, providing a fixed-measurement-point-free pose adjustment and positioning approach, and ensuring the full-process assembly efficiency for the three-dimensional part (3); moreover, a global coordinate system is established by means of laser trackers (1), improving the measurement precision and ensuring the measurement reliability.

Description

A method for attitude adjustment and positioning without fixed measurement points for large-scale three-dimensional assembly Technical Field

[0001] The present invention relates to the technical field of large-scale three-dimensional digital processing and assembly, and in particular to a posture adjustment and positioning method for large-scale three-dimensional assembly without fixed measuring points. Background Art

[0002] In the field of large-scale three-dimensional digital processing / assembly, CNC positioners are generally used to support three-dimensional components. Measurement points are arranged on the three-dimensional components and given theoretical point coordinates. The position coordinates of the measurement points are measured by a laser tracker in the component's current state. The CNC positioner is controlled to move toward the theoretical posture based on the position deviation between the current state and the theoretical state, and finally the three-dimensional component is adjusted to the theoretical posture. During the entire process, a large number of measurement points need to be arranged in the early stage, which is very time-consuming. At the same time, each point needs to be constrained accordingly, which may cause the point position to be over-constrained to a large extent. Moreover, every point needs to be measured during the measurement, which seriously affects the efficiency of the measurement and even the efficiency of the entire three-dimensional component assembly process.

[0003] Summary of the Invention

[0004] In response to the problem that a large number of measuring points need to be arranged in the early stage of the existing attitude adjustment and positioning method, which seriously affects the measurement efficiency and even the efficiency of the entire three-dimensional component assembly process, the present invention proposes a attitude adjustment and positioning method without fixed measuring points for large-scale three-dimensional assembly; by adopting a method without fixed measuring points, the steps of arranging measuring points on various planes in the early stage of large three-dimensional components are reduced, the measurement efficiency of three-dimensional components is improved, and the influence of point over-constraint is reduced, and an attitude adjustment and positioning method without fixed measuring points is provided, thereby ensuring the assembly efficiency of the three-dimensional components throughout the entire process; and a global coordinate system is established by a laser tracker, which improves the measurement precision and ensures the accuracy of the measurement.

[0005] The specific implementation contents of the present invention are as follows:

[0006] A method for adjusting and positioning a large-scale three-dimensional assembly without fixed measurement points specifically comprises the following steps:

[0007] Step S1: using a laser tracker to construct a global coordinate system on the plane of the three-dimensional component, determine the theoretical state of the three-dimensional component, and construct a theoretical plane normal vector matrix;

[0008] Step S2: installing a numerical control positioner at the bottom of the three-dimensional component, arbitrarily selecting n points on the plane of the three-dimensional component, measuring the position coordinates of the n points in the current state, and obtaining the plane normal vector matrix in the current state;

[0009] Step S3: Based on the theoretical plane normal vector matrix and the plane normal vector matrix in the current state, a singular value decomposition method is used to obtain a posture rotation matrix of the three-dimensional component from the current state to the theoretical state, and a numerical control positioner is driven to rotate the three-dimensional component according to the posture rotation matrix;

[0010] Step S4: randomly selecting n points on the plane of the rotated three-dimensional component, measuring the position coordinates of the n points in the current state, obtaining the normal vector matrix of the rotated plane, and calculating the vector angle between the theoretical plane and the rotated plane;

[0011] Step S5: Calculate the angle error according to the vector angle, and determine whether the angle error meets the error tolerance according to the set tolerance value. If not, return to step S2; if yes, execute step S6;

[0012] Step S6: Solve the intersection of the plane of the rotated three-dimensional component and the coordinate axis of the global coordinate system, calculate the translation along the direction axis, call the CNC positioner to translate the three-dimensional component, calculate the error intersection matrix of the intersection of the translated plane and the coordinate axis and the intersection of the theoretical plane and the coordinate axis, and adjust the posture and position the three-dimensional component.

[0013] In order to better implement the present invention, further, step S1 specifically includes the following steps:

[0014] Step S11: constructing a global coordinate system on the plane of the three-dimensional component using a laser tracker, and determining a theoretical state of the three-dimensional component according to the global coordinate system;

[0015] Step S12: constructing a theoretical plane equation of the three-dimensional component according to the theoretical state of the three-dimensional component;

[0016] Step S13: Solve the theoretical plane equation of the three-dimensional component to obtain the normal vector of the plane in the theoretical state, and construct the theoretical plane normal vector matrix V t ;

[0017] Step S14: According to the theoretical plane normal vector matrix V t , calculate the intersection coordinates of the theoretical plane and the coordinate axis of the global coordinate system, and obtain the intersection theoretical matrix Q of the theoretical plane and the coordinate axis according to the intersection coordinates t .

[0018] In order to better implement the present invention, further, step S2 specifically includes the following steps:

[0019] Step S21: installing a numerical control positioner at the bottom of the three-dimensional component, and arbitrarily selecting n points on the plane j of the three-dimensional component according to the laser tracker;

[0020] Step S22: Measure the position coordinates of n points in the current state and obtain the coordinate matrix PC j ;

[0021] Step S23: According to the coordinate matrix PC j , get the plane fitting equation of plane j;

[0022] Step S24: Calculate the plane normal vector matrix V according to the plane fitting equation p .

[0023] In order to better implement the present invention, further, step S3 specifically includes the following steps:

[0024] Step S31: According to the theoretical plane normal vector matrix V t and the plane normal matrix V p , calculate the rotation around the three coordinate axes of the global coordinate system;

[0025] Step S32: Call the singular value decomposition method to obtain the posture rotation matrix R of the three-dimensional component from the current state to the theoretical state pt ; Step S33: Rotate the matrix R according to the posture pt Drive the CNC positioner to rotate the three-dimensional parts.

[0026] In order to better implement the present invention, further, step S4 specifically includes the following steps:

[0027] Step S41: randomly select n points on the plane of the rotated three-dimensional component, measure the position coordinates of the n points in the current state, and obtain the coordinate matrix PC j ';

[0028] Step S42: According to the coordinate matrix PC j ', get the plane fitting equation of the rotated plane j;

[0029] Step S43: Obtain the rotated plane normal vector matrix V according to the rotated plane fitting equation p ', calculate the vector angle between the theoretical plane and the rotated plane.

[0030] In order to better implement the present invention, further, step S6 specifically includes the following steps:

[0031] Step S61: Calculate the intersection of the plane of the rotated three-dimensional component and the coordinate axis of the global coordinate system that meets the error tolerance, and obtain the theoretical intersection matrix Q of the theoretical plane and the coordinate axis. N ;

[0032] Step S62: According to the intersection theory matrix Q N, calculate the translation along the direction axis;

[0033] Step S63: Call the CNC positioner to translate the three-dimensional component according to the translation amount, select n points arbitrarily on the plane of the translated three-dimensional component, measure the position coordinates of the n points in the current state, and obtain the coordinate matrix PC j ”;

[0034] Step S64: According to the coordinate matrix PC j ", get the plane fitting equation of the translated plane j;

[0035] Step S65: According to the plane fitting equation after translation, solve the intersection of the translated plane j and the global coordinate system to obtain the intersection matrix Q F ;

[0036] Step S66: According to the intersection matrix Q F , calculate the error intersection matrix ef between the intersection of the translated plane j and the coordinate axis and the intersection of the theoretical plane and the coordinate axis, and obtain the position error tolerance;

[0037] Step S67: If the position error tolerance meets the error tolerance requirement, the posture adjustment and positioning of the three-dimensional component is completed; if it does not meet the error tolerance requirement, return to step S21.

[0038] The present invention has the following beneficial effects:

[0039] (1) The present invention reduces the steps of arranging measurement points on various planes in the early stage of large three-dimensional components by adopting a posture adjustment and positioning method without fixed measurement points, improves the measurement efficiency of components, and reduces the influence of point over-constraint. It provides a posture adjustment and positioning method without fixed measurement points, and ensures the assembly efficiency of three-dimensional components throughout the entire process.

[0040] (2) The present invention adopts a laser tracker for measurement, which has high measurement accuracy and stable performance, can adapt to complex processing environments, and ensures the accuracy of the measured values; it is suitable for arbitrary plane fitting and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG1 is a diagram showing the posture of a three-dimensional component supported by a numerically controlled positioner provided by the present invention in global coordinates.

[0042] FIG2 is a j-th planar schematic diagram of the three-dimensional component provided by the present invention in its current posture.

[0043] FIG3 is a j-th planar schematic diagram of the three-dimensional component provided by the present invention after rotation.

[0044] FIG4 is a j-th planar schematic diagram of the three-dimensional component provided by the present invention after translation.

[0045] FIG5 is a schematic diagram of the theoretical state and actual support state of the three-dimensional component provided by the present invention.

[0046] 1. Laser tracker, 2. CNC positioner, 3. Three-dimensional components. DETAILED DESCRIPTION

[0047] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be understood that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and therefore should not be regarded as limiting the scope of protection. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technical personnel in this field without making creative work are within the scope of protection of the present invention.

[0048] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "disposed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0049] Example 1:

[0050] This embodiment proposes a posture adjustment and positioning method for large-scale three-dimensional assembly without fixed measurement points, which specifically includes the following steps: Step S1: Use the laser tracker 1 to construct a global coordinate system in the plane of the three-dimensional component 3, determine the theoretical state of the three-dimensional component 3, and construct a theoretical plane normal vector matrix.

[0051] The step S1 specifically includes the following steps:

[0052] Step S11: constructing a global coordinate system on the plane of the three-dimensional component 3 using the laser tracker 1, and determining a theoretical state of the three-dimensional component 3 according to the global coordinate system;

[0053] Step S12: constructing a theoretical plane equation of the three-dimensional component according to the theoretical state of the three-dimensional component 3;

[0054] Step S13: Solve the theoretical plane equation of the three-dimensional component to obtain the normal vector of the plane in the theoretical state, and construct the theoretical plane normal vector matrix V t ;

[0055] Step S14: According to the theoretical plane normal vector matrix V t, calculate the intersection coordinates of the theoretical plane and the coordinate axis of the global coordinate system, and obtain the intersection theoretical matrix Q of the theoretical plane and the coordinate axis according to the intersection coordinates t .

[0056] Step S2: Install a CNC positioner 2 at the bottom of the three-dimensional component 3, select n points arbitrarily on the plane of the three-dimensional component 3, measure the position coordinates of the n points in the current state, and obtain the plane normal vector matrix in the current state.

[0057] The step S2 specifically includes the following steps:

[0058] Step S21: Installing a numerical control positioner 2 at the bottom of the three-dimensional component 3, and arbitrarily selecting n points on the plane j of the three-dimensional component 3 according to the laser tracker 1;

[0059] Step S22: Measure the position coordinates of n points in the current state and obtain the coordinate matrix PC j ;

[0060] Step S23: According to the coordinate matrix PC j , get the plane fitting equation of plane j;

[0061] Step S24: Calculate the plane normal vector matrix V according to the plane fitting equation p .

[0062] Step S3: Based on the theoretical plane normal vector matrix and the plane normal vector matrix in the current state, the singular value decomposition method is called to obtain the posture rotation matrix of the three-dimensional component 3 from the current state to the theoretical state, and the CNC positioner 2 is driven to rotate the three-dimensional component 3 according to the posture rotation matrix.

[0063] Furthermore, the step S3 specifically includes the following steps:

[0064] Step S31: According to the theoretical plane normal vector matrix V t and the plane normal matrix V p , calculate the rotation around the three coordinate axes of the global coordinate system;

[0065] Step S32: Call the singular value decomposition method to obtain the posture rotation matrix R of the three-dimensional component 3 from the current state to the theoretical state pt ; Step S33: Rotate the matrix R according to the posture pt The CNC positioner 2 is driven to rotate the three-dimensional component 3 .

[0066] Step S4: randomly select n points on the plane of the rotated three-dimensional component 3, measure the position coordinates of the n points in the current state, obtain the normal vector matrix of the rotated plane, and calculate the vector angle between the theoretical plane and the rotated plane.

[0067] The step S4 specifically includes the following steps:

[0068] Step S41: randomly select n points on the plane of the rotated three-dimensional component 3, measure the position coordinates of the n points in the current state, and obtain the coordinate matrix PC i ';

[0069] Step S42: According to the coordinate matrix PC j ', get the plane fitting equation of the rotated plane j;

[0070] Step S43: Obtain the rotated plane normal vector matrix V according to the rotated plane fitting equation p ', calculate the vector angle between the theoretical plane and the rotated plane.

[0071] Step S5: Calculate the angle error based on the vector angle, and determine whether the angle error meets the error tolerance based on the set tolerance value. If not, return to step S2; if yes, execute step S6.

[0072] Step S6: Solve the intersection of the plane of the rotated three-dimensional component 3 and the coordinate axis of the global coordinate system, calculate the translation along the direction axis, call the CNC positioner 2 to translate the three-dimensional component 3, calculate the error intersection matrix of the intersection of the translated plane and the coordinate axis and the intersection of the theoretical plane and the coordinate axis, and adjust the posture and position the three-dimensional component 3.

[0073] Furthermore, step S6 specifically includes the following steps:

[0074] Step S61: Calculate the intersection of the plane of the rotated three-dimensional component 3 and the coordinate axis of the global coordinate system that meets the error tolerance, and obtain the theoretical intersection matrix Q of the theoretical plane and the coordinate axis. N ;

[0075] Step S62: According to the intersection theory matrix Q N , calculate the translation along the direction axis;

[0076] Step S63: Call the CNC positioner 2 to translate the three-dimensional component 3 according to the translation amount, select n points arbitrarily on the plane of the translated three-dimensional component 3, measure the position coordinates of the n points in the current state, and obtain the coordinate matrix PC j ”;

[0077] Step S64: According to the coordinate matrix PC j", get the plane fitting equation of the translated plane j;

[0078] Step S65: According to the plane fitting equation after translation, solve the intersection of the translated plane j and the global coordinate system to obtain the intersection matrix Q F ;

[0079] Step S66: According to the intersection matrix Q F , calculate the error intersection matrix ef between the intersection of the translated plane j and the coordinate axis and the intersection of the theoretical plane and the coordinate axis, and obtain the position error tolerance;

[0080] Step S67: If the position error tolerance meets the error tolerance requirement, the posture adjustment and positioning of the three-dimensional component 3 is completed; if it does not meet the error tolerance requirement, return to step S21.

[0081] Working principle: This embodiment first uses a laser tracker 1 to construct a global coordinate system on the plane of the three-dimensional component 3, determines the theoretical state of the three-dimensional component 3, and constructs a theoretical plane normal vector matrix; secondly, a CNC positioner 2 is installed at the bottom of the three-dimensional component 3, and n points are arbitrarily selected on the plane of the three-dimensional component 3, and the position coordinates of the n points in the current state are measured to obtain the plane normal vector matrix in the current state; then, based on the theoretical plane normal vector matrix and the plane normal vector matrix in the current state, the singular value decomposition method is called to obtain the posture rotation matrix of the three-dimensional component 3 from the current state to the theoretical state, and the CNC positioner 2 is driven to rotate the three-dimensional component 3 according to the posture rotation matrix; and n points are arbitrarily selected on the plane of the rotated three-dimensional component 3, and the position coordinates of the n points in the current state are measured to obtain the rotated plane normal vector matrix. Calculate the vector angle between the theoretical plane and the rotated plane; then calculate the angular error based on the vector angle, and determine whether the angular error meets the error tolerance based on the set tolerance value. If not, return to step S2; if yes, execute step S6; finally, solve the intersection of the plane of the rotated three-dimensional component 3 and the coordinate axis of the global coordinate system, calculate the translation along the direction axis, call the CNC positioner 2 to translate the three-dimensional component 3, calculate the error intersection matrix of the intersection of the translated plane and the coordinate axis and the intersection of the theoretical plane and the coordinate axis, and adjust the posture and position the three-dimensional component 3; by adopting a method without fixed measurement points, the work of arranging measurement points on the component plane in the early stage is reduced, and there is no need to find fixed measurement points. The measurement can be quickly realized, which improves the working efficiency. The laser tracker 1 is used for measurement, which has high measurement accuracy and stable performance, can adapt to complex processing environments, and ensure the accuracy of the measurement value.

[0082] Example 2:

[0083] This embodiment is based on the above embodiment 1 and is described in detail with a specific embodiment as shown in Figures 1, 2, 3, 4 and 5.

[0084] The specific implementation steps are as follows:

[0085] Step 1: As shown in FIG1 , no fixed measurement points are arranged on each plane of the three-dimensional component 3 , and a global coordinate system is established using a laser tracker 1 , and the theoretical state of the three-dimensional component 3 is determined based on the global coordinate system.

[0086] The laser tracker 1 used in this embodiment has stable performance and can adapt to harsh environments.

[0087] Step 2: Based on the theoretical state of the three-dimensional component 3 described in Step 1, since plane BCGH is at the bottom of the three-dimensional component 3 and is difficult to measure, FIG1 can be used to analyze and describe the three-dimensional component 3 using other planes. As shown in FIG2 , the theoretical plane equations of the remaining planes of the component are determined and the following description is provided.

[0088] Theoretical plane 1: W t1 x+S t1 y+T t1 z+U t1 =0;

[0089] Theoretical plane 2: W t2 x+S t2 y+T t2 z+U t2 =0;

[0090] Theoretical plane 3: W t3 x+S t3 y+T t3 z+U t3 =0;

[0091] Theoretical plane 4: W t4 x+S t4 y+T t4 z+U t4 =0;

[0092] Theoretical plane 5: W t5 x+S t5 y+T t5 z+U t5 =0;

[0093] W above ti 、S ti、 T ti、 U tiAll are not 0, where i = 1, 2, 3, 4, 5; theoretical plane 1 represents plane ABCD, theoretical plane 2 represents plane EFAD, theoretical plane 3 represents plane EFGH, theoretical plane 4 represents plane AEHB, and theoretical plane 5 represents plane DFGC.

[0094] Step 3: Solve the normal vectors of each plane in the theoretical state through the theoretical plane equation of the three-dimensional component, describe it with a correlation matrix, and calculate the coordinates of the intersection of each theoretical plane and each coordinate axis of the global coordinate system, and express them with a correlation matrix;

[0095] Theoretical plane normal matrix:

[0096] The theoretical intersection of the theoretical plane and the X-axis of the global coordinate system is:

[0097] The theoretical intersection of the theoretical plane and the Y axis of the global coordinate system is:

[0098] The theoretical intersection of the theoretical plane and the Z axis of the global coordinate system is:

[0099] Where i = 1, 2, 3, 4, 5;

[0100] Theoretical matrix of the intersection of the theoretical plane and the coordinate axis:

[0101] Step 4: Use a set of CNC positioners 2 to support the three-dimensional component 3. In the current state of the three-dimensional component, use the laser tracker 1 to find n points on each plane of the component and measure them. The position coordinates of the current n points in the current state are measured and recorded using a correlation matrix.

[0102] In this embodiment, a set of four CNC positioners 2 is provided; n ≥ 3. They cannot be arranged in a straight line, as shown in Figure 2 , and should be arranged as close to the entire plane as possible. In this embodiment, each face of the three-dimensional component 3 is planar, and at least three planes must be evaluated, all of which must be skewed.

[0103] The numerical control positioner 2 provided in this embodiment meets various accuracy indicators, including spatial positioning accuracy, repeat positioning accuracy, and geometric accuracy.

[0104] Each plane has i measurement points, i = 3, 4, 5, 6..., n;

[0105] Among them, PC j The matrix composed of n points representing the j-th plane, j = 1, 2, 3, 4, 5.

[0106] Step 5: Using the current coordinates of the n measurement points on each plane of the three-dimensional component 3 in step 4, fit the current plane equation of each plane;

[0107] The j-th plane fitting equation, j = 1, 2, 3, 4, 5; W Pj x+S Pj y+T Pj z+U Pj =0

[0108] in:

[0109] Step 6: Calculate the normal vector of each plane using the plane equation of the three-dimensional component 3 in the current state in step 5 and the quadrant judgment rule based on the normal vector, and describe it using a matrix;

[0110] Step 7: Using the normal vectors of each plane of the three-dimensional component 3 in the theoretical state in step 3 and the normal vectors of each plane in the actual state calculated in step 6, the traditional singular value decomposition method is used to solve the rotation matrix of the three-dimensional component 3 from the current state to the theoretical state. At the same time, the attitude rotation matrix R pt It is expressed as follows;

[0111] where α pt， β pt， γ pt They are the rotation amounts around the three coordinate axes of the global coordinate system.

[0112] Step 8: Using the posture rotation matrix calculated in step 7, drive the current CNC positioner 2 to rotate the three-dimensional component 3;

[0113] Step 9, as shown in FIG3 , uses the laser tracker 1 to measure n points found arbitrarily on each plane of the three-dimensional component 3 after the rotational motion, then performs plane fitting as in step 5, and calculates the normal vectors of each plane using the method of step 6; uses the theoretical normal vectors of each plane of the three-dimensional component 3 calculated in step 3 and the plane normal vectors calculated by the measurement after the rotation to perform angle analysis to evaluate the angle error between vectors; in this embodiment, n ≥ 3, and cannot be on a straight line, and should be arranged as far as possible to accurately describe the entire plane.

[0114] Fitting the j-th plane equation, j = 1, 2, 3, 4, 5: WNj x+S Nj y+T Nj z+U Nj =0;

[0115] The normal vector matrix of each plane of the three-dimensional component 3 after posture adjustment:

[0116] The vector angle between the theoretical plane and the measured plane, j = 1, 2, 3, 4, 5:

[0117] Step 10: If the angle error is evaluated in step 9 and meets the error tolerance requirements, proceed to the next step; if the tolerance does not meet the requirements, proceed to steps 4 to 9; j =|1-θ j |≤ξ j

[0118] Among them, ξ j is the tolerance value for angle evaluation.

[0119] Step 11: according to the fitting planes of the rotated three-dimensional component 3 calculated in step 10, the intersection points of each plane and the coordinate axis of the coordinate system are solved;

[0120] The theoretical intersection of the theoretical plane and the X-axis of the global coordinate system is:

[0121] The theoretical intersection of the theoretical plane and the Y axis of the global coordinate system is:

[0122] The theoretical intersection of the theoretical plane and the Z axis of the global coordinate system is:

[0123] where j = 1, 2, 3, 4, 5;

[0124] Theoretical matrix of the intersection of the theoretical plane and the coordinate axis:

[0125] Amount of translation along X:

[0126] Y translation:

[0127] Amount of translation along Z:

[0128] Step 12: By using the CNC positioner 2 and the translation amounts along each coordinate axis calculated in step 11, the three-dimensional component 3 is subjected to corresponding translational motion. After the motion is completed, the laser tracker 1 is used to measure n points found arbitrarily on each plane of the three-dimensional component 3, as shown in FIG4 . The measured coordinates are used to fit each plane in the current state, and the intersection points of each plane with the coordinate axis of the coordinate system are solved. Finally, the position error analysis and evaluation are performed. In this embodiment, n ≥ 3, and it cannot be on a straight line. Try to arrange it in a place that can accurately describe the entire plane.

[0129] According to the above method steps 9 and 11, the intersection of the plane and the coordinate axis of the coordinate system is obtained, and the intersection matrix is ​​obtained:

[0130] The error intersection matrix of the intersection of the theoretical plane and the coordinate axis and the intersection of the fitted plane and the coordinate axis:

[0131] in:

[0132] i=1, 2, 3, 4, 5.

[0133] Step 13: If the position error evaluation in step 12 meets the error tolerance requirement, the attitude adjustment and positioning of the three-dimensional component 3 is completed; if the tolerance does not meet the requirement, the method of steps 10 to 12 is repeated; e fxj ≤ξ xj e fyj ≤ξ yj e fzj ≤ξ zj

[0134] where ξ xj ,ξ yj ,ξ zj For given tolerances, j = 1, 2, 3, 4, 5.

[0135] Working principle: The posture adjustment and positioning method without fixed measuring points proposed in this embodiment for large-scale three-dimensional assembly reduces the steps of arranging measuring points on various planes in the early stage of large three-dimensional components, improves the measurement efficiency of components, and at the same time reduces the impact of point over-constraints, provides a posture adjustment and positioning method without fixed measuring points, and ensures the assembly efficiency of the three-dimensional component 3 throughout the entire process.

[0136] The rest of this embodiment is the same as that of the above-mentioned embodiment 1, and therefore will not be described in detail.

[0137] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A method for adjusting and positioning postures of large-scale three-dimensional assemblies without fixed measurement points, characterized in that: The specific steps include: Step S1: using a laser tracker (1) to construct a global coordinate system on the plane of the three-dimensional component (3), determining the theoretical state of the three-dimensional component (3), and constructing a theoretical plane normal vector matrix; Step S2: installing a numerical control positioner (2) at the bottom of the three-dimensional component (3), arbitrarily selecting n points on the plane of the three-dimensional component (3), measuring the position coordinates of the n points in the current state, and obtaining the plane normal vector matrix in the current state; Step S3: Based on the theoretical plane normal vector matrix and the plane normal vector matrix in the current state, a singular value decomposition method is called to obtain a posture rotation matrix of the three-dimensional component (3) from the current state to the theoretical state, and a numerical control positioner (2) is driven to rotate the three-dimensional component (3) according to the posture rotation matrix; Step S4: randomly selecting n points on the plane of the rotated three-dimensional component (3), measuring the position coordinates of the n points in the current state, obtaining a normal vector matrix of the rotated plane, and calculating the vector angle between the theoretical plane and the rotated plane; Step S5: Calculate the angle error according to the vector angle, and determine whether the angle error meets the error tolerance according to the set tolerance value. If not, return to step S2; if yes, execute step S6; Step S6: solve the intersection of the plane of the rotated three-dimensional component (3) and the coordinate axis of the global coordinate system, calculate the translation along the direction axis, call the CNC positioner (2) to translate the three-dimensional component (3), calculate the error intersection matrix of the intersection of the translated plane and the coordinate axis and the intersection of the theoretical plane and the coordinate axis, and adjust the posture and position the three-dimensional component (3).

2. The method for adjusting and positioning a large-scale three-dimensional assembly without fixed measurement points according to claim 1, characterized in that: The step S1 specifically includes the following steps: Step S11: using the laser tracker (1) to construct a global coordinate system on the plane of the three-dimensional component (3), and determining the theoretical state of the three-dimensional component (3) according to the global coordinate system; Step S12: constructing a theoretical plane equation of the three-dimensional component according to the theoretical state of the three-dimensional component (3); Step S13: Solve the theoretical plane equation of the three-dimensional component to obtain the normal vector of the plane in the theoretical state, and construct the theoretical plane normal vector matrix V t ; Step S14: According to the theoretical plane normal vector matrix V t , calculate the intersection coordinates of the theoretical plane and the coordinate axis of the global coordinate system, and obtain the intersection theoretical matrix Q of the theoretical plane and the coordinate axis according to the intersection coordinates t .

3. The method for adjusting and positioning a large-scale three-dimensional assembly without fixed measurement points according to claim 2, characterized in that: The step S2 specifically includes the following steps: Step S21: Install a numerical control positioner (2) at the bottom of the three-dimensional component (3), and use the laser tracker (1) to Arbitrarily select n points on the plane j of the three-dimensional component (3); Step S22: Measure the position coordinates of n points in the current state and obtain the coordinate matrix PC j ; Step S23: According to the coordinate matrix PC j , get the plane fitting equation of plane j; Step S24: Calculate the plane normal vector matrix V according to the plane fitting equation p .

4. The method for adjusting and positioning a large-scale three-dimensional assembly without fixed measurement points according to claim 3, characterized in that: The step S3 specifically includes the following steps: Step S31: According to the theoretical plane normal vector matrix V t and the plane normal matrix V p , calculate the rotation around the three coordinate axes of the global coordinate system; Step S32: Call the singular value decomposition method to obtain the posture rotation matrix R of the three-dimensional component (3) from the current state to the theoretical state pt ; Step S33: Rotate the matrix R according to the posture pt A numerical control positioner (2) is driven to rotate the three-dimensional component (3).

5. The method for adjusting and positioning a large-scale three-dimensional assembly without fixed measurement points according to claim 4, characterized in that: The step S4 specifically includes the following steps: Step S41: randomly select n points on the plane of the rotated three-dimensional component (3), measure the position coordinates of the n points in the current state, and obtain the coordinate matrix PC j '; Step S42: According to the coordinate matrix PC j ', get the plane fitting equation of the rotated plane j; Step S43: Obtain the rotated plane normal vector matrix V according to the rotated plane fitting equation p ', calculate the vector angle between the theoretical plane and the rotated plane.

6. The method for adjusting and positioning posture of a large-scale three-dimensional assembly without fixed measurement points according to claim 5, characterized in that: The step S6 specifically includes the following steps: Step S61: Calculate the intersection of the plane of the rotated three-dimensional component (3) and the coordinate axis of the global coordinate system that meets the error tolerance, and obtain the theoretical intersection matrix Q of the theoretical plane and the coordinate axis. N ; Step S62: According to the intersection theory matrix Q N , calculate the translation along the direction axis; Step S63: Call the numerical control positioner (2) to translate the three-dimensional component (3) according to the translation amount, select n points arbitrarily on the plane of the translated three-dimensional component (3), measure the position coordinates of the n points in the current state, and obtain the coordinate matrix PC j ”; Step S64: According to the coordinate matrix PC j ", get the plane fitting equation of the translated plane j; Step S65: According to the plane fitting equation after translation, solve the intersection of the translated plane j and the global coordinate system to obtain the intersection matrix Q F ; Step S66: According to the intersection matrix Q F , calculate the intersection of the translated plane j and the coordinate axis and the intersection of the theoretical plane and the coordinate axis The error intersection matrix ef of the intersection point is used to obtain the position error tolerance; Step S67: If the position error tolerance meets the error tolerance requirement, the posture adjustment and positioning of the three-dimensional component (3) is completed; if it does not meet the error tolerance requirement, return to step S21.

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